libquadmath/math/ceilq.c

   1 /* ceilq.c -- __float128 version of s_ceil.c.
   2  * Conversion to IEEE quad long double by Jakub Jelinek, jj@ultra.linux.cz.
   3  */
   4
   5 /*
   6  * ====================================================
   7  * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
   8  *
   9  * Developed at SunPro, a Sun Microsystems, Inc. business.
  10  * Permission to use, copy, modify, and distribute this
  11  * software is freely granted, provided that this notice
  12  * is preserved.
  13  * ====================================================
  14  */
  15
  16 #include "quadmath-imp.h"
  17
  18 __float128
  19 ceilq (__float128 x)
  20 {
  21         int64_t i0,i1,j0;
  22         uint64_t i,j;
  23         GET_FLT128_WORDS64(i0,i1,x);
  24         j0 = ((i0>>48)&0x7fff)-0x3fff;
  25         if(j0<48) {
  26             if(j0<0) {
  27                 /* return 0*sign(x) if |x|<1 */
  28                 if(i0<0) {i0=0x8000000000000000ULL;i1=0;}
  29                 else if((i0|i1)!=0) { i0=0x3fff000000000000ULL;i1=0;}
  30             } else {
  31                 i = (0x0000ffffffffffffULL)>>j0;
  32                 if(((i0&i)|i1)==0) return x; /* x is integral */
  33                 if(i0>0) i0 += (0x0001000000000000LL)>>j0;
  34                 i0 &= (~i); i1=0;
  35             }
  36         } else if (j0>111) {
  37             if(j0==0x4000) return x+x;  /* inf or NaN */
  38             else return x;              /* x is integral */
  39         } else {
  40             i = -1ULL>>(j0-48);
  41             if((i1&i)==0) return x;     /* x is integral */
  42             if(i0>0) {
  43                 if(j0==48) i0+=1;
  44                 else {
  45                     j = i1+(1LL<<(112-j0));
  46                     if(j<i1) i0 +=1 ;   /* got a carry */
  47                     i1=j;
  48                 }
  49             }
  50             i1 &= (~i);
  51         }
  52         SET_FLT128_WORDS64(x,i0,i1);
  53         return x;
  54 }